eff

Verb (usu participle)

OXFORD DICTIONARY

eff, v. sl. euphem.
1 tr. & intr. (often foll. by off) = FUCK (in expletive use).
2 intr. say fuck or similar coarse slang words.

Idiom

effing and blinding using coarse slang.

Etymology

name of the letter F, as a euphemistic abbr.

For further exploring for "eff" in Webster Dictionary Online

Search Type	Description	Example
all	search for verses that contains all of the search words.	"fish bread" will search for verses that contains fish AND bread in minimum 1 bible version
phrase	search for verses that contains all of the search phrase.	"fish bread" will search for verses that contains "fish bread" in minimum 1 bible version
at least one	search for verses that contains any of the search words.	"fish bread" will search for verses that contains fish OR bread in minumum 1 bible version
without	search for verses not contained of the search words. Without can not be used by it self, meaning that it has to be minimum one more condition included (all/at least one,etc)	all: "fish", without: "bread", will search for verses that contains "fish" but NOT "bread"
start	search for verses that contains words that start with the search words	"fis" will search for verses that contains words start with "fis", the result will be "fish", "fishing", "fisherman", etc
similar	search for verses that contains words that similar in spelling to the search words.	"fish" will search verses that contain words which has similar spelling with fish. The result: "dish",etc
displaying	set the max displaying in one page.	"20" will set displaying max to 20 per page
range	set searching range	"All Bible", "Old Testament", "New Testament"

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